Selecting buckets for redistributing data between nodes in a parallel database in the quiescent mode
AssigneeInternational Business Machines Corporation
InventorShih-Gong Li
Life of this patent
Estimating the term…
Abstract
A method, system and program for determining which data stored in the nodes in a parallel database to redistribute to a receiving node. First, an average workload for the nodes within the parallel database is calculated based on the total workload divided by the number of existing and new nodes. Next, a set of transmitting nodes is established each of which has a workload which exceeds the average workload. A set of data structures which when redistributed from the transmitting node to the receiving node will lower the transmitting node workload to equal or slightly greater than the average workload is selected. Finally, the set of data structures is redistributed from the transmitting node to the receiving node.
Claims15
A method for determining which data stored in the nodes in a parallel database system to redistribute to a receiving node, comprising the steps of:
- calculating an average workload for the nodes within the parallel database system;
- determining a transmitting node having a workload which exceeds the average workload;
- selecting redistributable data which when redistributed from the transmitting node to the receiving node will lower the transmitting node workload toward the average workload;
- and
- redistributing the redistributable data from the transmitting node to the receiving node.
A system for determining which data stored in the nodes in a parallel database system to redistribute to a receiving node, comprising:
- means for calculating an average workload for the nodes within the parallel database;
- means for determining a transmitting node having a workload which exceeds the average workload;
- means for selecting redistributable data which when redistributed from the transmitting node to the receiving node will lower the transmitting node workload toward the average workload;
- and
- means for redistributing the redistributable data from the transmitting node to the receiving node.
A computer program product in a computer readable memory for determining which data stored in the nodes in a parallel database system to redistribute to a receiving node, comprising:
- means for calculating an average workload for the nodes within the parallel database;
- means for determining a transmitting node having a workload which exceeds the average workload;
- means for selecting redistributable data which when redistributed from the transmitting node to the receiving node will lower the transmitting node workload toward the average workload;
- and
- means for redistributing the redistributable data from the transmitting node to the receiving node.
Dependencies are inferred from the claim text.